Dice yellow squash, zucchini, carrots, red onion.
Combine yellow squash, zucchini, carrots, red onion and dill and mix well together.
Over low heat, combine vinegar, sugar, mustard seed, coriander seed, salt and red pepper in small sauce pan.
Cook until sugar dissolves, approximately 3 minutes
Pour over vegetable mixture, and toss until all pieces are well coated.